Bida G T, Ehrenkaufer R L, Wolf A P, Fowler J S, MacGregor R R, Ruth T J
J Nucl Med. 1980 Aug;21(8):758-62.
Irradiation of gas mixtures of F2/Ne (20Ne leads to d,alpha 18F) which contained percent levels ( > 0.1%) of N2, CO2, CO2, or CF4 resulted in the production of unacceptable levels of F-18-labeled NF3 and CF4 at the expense of 18F-F2. Analycical gas chromatographic methods have been devised to determine contaminant levels in the target gas as well as in the products arising from them. Commercial mixtures of 1T F2/Ne, pur F2, and neon have been analyzed for contaminants (N2, O2, CO, CO2, and CF4) and found to vary widely in the levels of these impurities from batch to batch. The N2 levels in the 1% F2/Ne mixtures varied from 0.039 to 0.49%, and the CO2 levels from 0o.018 to 0.13%. No detectable impurities were found in the neon (Research Purity), but F2 was found to contain approximately 11% CF4. Reproducibly high yields of 18F-F2 are obtained if the levels of N2, CO2, and CF4 in the final target gas mixture are < 0.01% and carrier F2 is approximately 0.1%. Hydrocarbons and CO were not detected in our gas mixtures, but would also be expected to decrease yields of 18F-F2.
对含有百分含量水平（>0.1%）的N₂、CO₂、CO或CF₄的F₂/Ne（²⁰Ne产生d、α ¹⁸F）气体混合物进行辐照，会导致以¹⁸F-F₂为代价产生不可接受水平的¹⁸F标记的NF₃和CF₄。已经设计了分析气相色谱方法来测定目标气体以及由其产生的产物中的污染物水平。对1% F₂/Ne、纯F₂和氖气的商业混合物进行了污染物（N₂、O₂、CO、CO₂和CF₄）分析，发现这些杂质的含量在不同批次之间差异很大。1% F₂/Ne混合物中的N₂含量在0.039%至0.49%之间变化，CO₂含量在0.018%至0.13%之间变化。在氖气（研究级纯度）中未发现可检测到的杂质，但发现F₂中含有约11%的CF₄。如果最终目标气体混合物中N₂、CO₂和CF₄的含量<0.01%且载体F₂约为0.1%，则可重复获得高产率的¹⁸F-F₂。在我们的气体混合物中未检测到碳氢化合物和CO，但预计它们也会降低¹⁸F-F₂的产率。
